中介轴承环下流道滑油流动及润滑效率分析

航空发动机主轴轴承（中介轴承）大多采用环下供油方式进行润滑，滑油在环下供油流道中的流动特性影响着轴承润滑效率，为了改善迄今滑油流动分析与喷射-收纳滑油分析相割裂及未考虑环下供油孔与滚动体相对位置变化所产生滑油输出时变性影响的不足，提出了考虑滑油输出时变性影响的喷油-收油与滑油流动集成分析方法。首先，将进入环下供油流道的滑油分解为直接喷入收油孔的滑油和沉积于收油环壁面上并沿周向流入收油孔的滑油，通过计算这两部分滑油流量获得进入环下供油流道的滑油流量；然后，基于环下供油孔和滚动体相对位置变化规律确定供油孔出口的时变边界条件，将其嵌入滑油流动瞬态分析模型，进行模型求解后得到环下供油流道各出口的滑油流量及轴承润滑效率。所提出的滑油流动分析方法较为系统也更符合工程实际，为中介轴承润滑效率的准确计算提供了技术方法和基础数据，有助于中介轴承润滑系统的精确设计。

Inner ring oil flow and lubrication efficiency analysis of intershaft bearing

Inner ring oil flow lubrication is applied to principal bearing (intershaft bearing) of aero-engine. The oil-flow characteristics have an influence on lubrication efficiency of bearing. Previous studies have not considered the effect of time-varying oil outlet induced by positional variation between inner ring holes and rollers, and the oil spray-collection analysis is separated from oil flow analysis. To overcome the limitations above, this paper proposes an analytical method considering the effect of time-varying oil outlet, which integrates oil spray-collection and oil flow analysis. Firstly, the oil entering the inner ring tube is decomposed into the oil directly sprayed into tube as well as the oil deposited onto the solid wall and then flowing into the collection holes. By virtue of calculating those two parts of oil flow rates, flow rates of oil entering inner ring tube is obtained. Secondly, time-varying boundary conditions of inner ring holes are determined by positional variation rules of holes and rollers, and are then embedded into transient oil-flow analytical model that could be utilized to obtain the flow rates of each outlet and bearing lubrication efficiency. The proposed oil-flow analytical method is systematic and better qualified for engineering, providing technical method and basic data for the accurate calculation of lubrication efficiency and contributing to the precise design of the intershaft bearing lubrication system.